Caley Thistle had started the afternoon in third place, a point ahead of the Perth side, but Terry Butcher's side were leapfrogged as a result of losing the Highland derby.

Hasselbaink (right) added the second goal as Saints claimed victory over Motherwell

Nicky Law, playing in his final match for Motherwell, tried his luck early on for the visitors, but his hooked effort fell just wide.

Saints thought they had grabbed the opener after seven minutes when Steven MacLean connected with Hasselbaink's pass and sent an angled drive past Hollis, but it was ruled out for offside.

Without the experience of the suspended Frazer Wright in central defence, Saints manager Steve Lomas made three other changes from the side that lost 4-0 away to champions Celtic last time out.

After more than half an hour of undistinguished play on a difficult pitch that required the ball to be changed five times in an attempt to find a true roll, one of the replacements, Millar, went close to breaking the deadlock.

As the ball bobbled inside the Well penalty box, Millar's effort struck the face of a post before being cleared.

The visitors failed to heed the warning, however, and it was not long before Saints went ahead.

Craig, who has already agreed a pre-contract agreement with Scottish Premier League rivals Hibernian, gave the home fans a perfect leaving present.

His eighth goal of the season travelled a long way across the rutted McDiarmid Park turf before nestling in the corner of the net past Hollis.

Motherwell could have levelled on the stroke of half-time, but Alan Mannus saved well from Michael Higdon's header before Henrik Ojamaa blasted the rebound over.

Hollis, starting in place of Darren Randolph - who is poised to leave Fir Park after rejecting a new contract - was beaten again shortly after the interval.

Hasselbaink gathered a low pass into the box by Dave MacKay with his back to goal and his marker, but a swift swivel of his hips and a short backswing later the ball had travelled 15 yards into the corner of the net, with Hollis given no chance.

It was all Saints now and Murray Davidson, another player set to leave McDiarmid Park after rejecting the offer of a new deal, sent an effort against the crossbar.

But two goals were enough to deny Inverness third spot - and a place in Europe - for the first time in their history and send the Perth fans streaming onto the pitch to congratulate their players.